The Version 5 of the POLES model has been developed for the assessment of multi-gas emission reduction strategies. Abatement options have been introduced for all non-CO2 GHGs in the Kyoto Basket and, for the agricultural sector, Marginal Abatement Cost curves have been derived from the new AGRIPOL model. Combined with an international emission permit scheme that is based on the Soft Landing approach, an emission profile respecting climate targets of 550 ppmv provides a relatively soft constraint case for developing countries. The multi-gas analyses first of all demonstrate the relevance of the approach as changing from a CO2only to a multi-gas strategy either allows to increase total abatement of 25% for the same Marginal Abatement Cost or to decrease the MAC of approximately 30% for the same total abatement. Not surprisingly however, the impacts on world demand and primary fuel mix are less pronounced in the multi-gas case. This is easily understandable as a counterpart for introducing more margins of freedom in the abatement effort.